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1.
PLoS One ; 18(12): e0295566, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38134018

RESUMO

BACKGROUND: The purpose of this research was to verify that vericiguat, a soluble guanylate cyclase (sGC) stimulator, reduces myocardial ischemic reperfusion injury (MIRI), and to learn how this reduction happens. METHODS AND RESULTS: To develop an ischaemia/reperfusion (I/R) model, the left anterior descending artery was blocked in minipigs under anesthesia for 90 minutes, followed by 180 minutes of reperfusion. Vericiguat is administered three hours before surgery. Two weeks after receiving therapy, pigs underwent cardiovascular magnetic resonance imaging (MRI) to evaluate the results. The MRI results suggest improvement in the myocardial infarct after vericiguat treatment. Vericiguat treatment for two weeks enhanced vascularity, inhibited pro-inflammatory cells, and decreased collagen deposition in the infarct zone of pigs. Short-term experiments investigating possible explanations have indicated that vericiguat has antiapoptotic effects on cardiomyocytes and increases levels of autophagy. CONCLUSIONS: Vericiguat, an SGC activator, reduces MIRI in pigs by boosting autophagy, preventing apoptosis, and promoting angiogenesis.


Assuntos
Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Suínos , Animais , Porco Miniatura , Infarto do Miocárdio/patologia , Miócitos Cardíacos/patologia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/patologia , Reperfusão
2.
Sci Total Environ ; 902: 166045, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37544454

RESUMO

Waste plastics enter the environment (water, soil, and atmosphere) and degrade into micro- and nano-plastics (MNPs) through physical, chemical, or biological processes. MNPs are ubiquitous in the environment and inevitably interact with terrestrial plants. Terrestrial plants have become important potential sinks, and subsequently, the sources of MNPs. At present, many studies have reported the effects of MNPs on plant physiology, biochemistry, and their phototoxicity. However, the source, detection method, and the absorption process of MNPs in terrestrial plants have not been systematically studied. In order to better understand the continuous process of MNPs entering terrestrial plants, this review introduces the sources and analysis methods of MNPs in terrestrial plants. The uptake pathways of MNPs in terrestrial plants and their influencing factors were systematically summarized. Meanwhile, the transport pathways and the accumulation of MNPs in different plant organs (roots, stems, leaves, calyxes, and fruits) were explored. Finally, the transfer of MNPs through food chains to humans and their health risks were discussed. The aim of this work is to provide significant theoretical knowledge to understand the uptake, transport, and accumulation of MNPs in terrestrial plants and the potential health risks associated with their transfer to humans through food chain.


Assuntos
Plásticos , Poluentes Químicos da Água , Humanos , Plásticos/metabolismo , Cadeia Alimentar , Microplásticos/metabolismo , Plantas/metabolismo , Solo , Poluentes Químicos da Água/metabolismo
3.
J Hazard Mater ; 441: 129924, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36113347

RESUMO

Light rare earth elements (LREEs) have been long used in agriculture (i.e., mainly via aerially applied LREE fertilizers) based on the fact that low-dose LREEs promote plant growth. Meanwhile, the toxic effects of low-dose LREEs on organisms have also been found. However, the cellular and molecular mechanism of low-dose LREEs acting on organisms remain unclear. Plants are at the beginning of food chains, so it is critical to uncover the cellular and molecular mechanism of low-dose LREEs on plants. Here, lanthanum (La) and soybean were the representatives of LREEs and plants, respectively. The effects of low-dose La on soybean leaves were investigated, and the stimulatory effect and mechanism of low-dose LREEs on leaf cells were revealed. Specifically, clathrin-mediated endocytosis (CME) activated by low-dose La is an influx channel for La in soybean leaf cells. The intracellular La and La-activated CME jointly disturbed multiple forms of intracellular homeostasis, including metallic element homeostasis, redox homeostasis, gene expression homeostasis. The disturbed homeostasis either stimulated cell growth or caused damage to the plasma membrane of soybean leaf cells. These results provide new insights for clarifying the cellular and molecular mechanisms of low-dose LREEs as a class of stimulators instead of nutrients to stimulate plants.


Assuntos
Lantânio , Metais Terras Raras , Clatrina/metabolismo , Clatrina/farmacologia , Fertilizantes , Lantânio/toxicidade , Metais Terras Raras/metabolismo , Folhas de Planta/metabolismo , Plantas , Glycine max
4.
Comput Intell Neurosci ; 2021: 5631730, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868294

RESUMO

The motion intent recognition via lower limb prosthesis can be regarded as a kind of short-term action recognition, where the major issue is to explore the gait instantaneous conversion (known as transitional pattern) between each two adjacent different steady states of gait mode. Traditional intent recognition methods usually employ a set of statistical features to classify the transitional patterns. However, the statistical features of the short-term signals via the instantaneous conversion are empirically unstable, which may degrade the classification accuracy. Bearing this in mind, we introduce the one-dimensional dual-tree complex wavelet transform (1D-DTCWT) to address the motion intent recognition via lower limb prosthesis. On the one hand, the local analysis ability of the wavelet transform can amplify the instantaneous variation characteristics of gait information, making the extracted features of instantaneous pattern between two adjacent different steady states more stable. On the other hand, the translation invariance and direction selectivity of 1D-DTCWT can help to explore the continuous features of patterns, which better reflects the inherent continuity of human lower limb movements. In the experiments, we have recruited ten able-bodied subjects and one amputee subject and collected data by performing five steady states and eight transitional states. The experimental results show that the recognition accuracy of the able-bodied subjects has reached 98.91%, 98.92%, and 97.27% for the steady states, transitional states, and total motion states, respectively. Furthermore, the accuracy of the amputee has reached 100%, 91.16%, and 90.27% for the steady states, transitional states, and total motion states, respectively. The above evidence finally indicates that the proposed method can better explore the gait instantaneous conversion (better expressed as motion intent) between each two adjacent different steady states compared with the state-of-the-art.


Assuntos
Amputados , Membros Artificiais , Algoritmos , Humanos , Movimento (Física) , Análise de Ondaletas
5.
Ecotoxicol Environ Saf ; 221: 112429, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34147864

RESUMO

Rare earth elements (REEs) are emerging as a serious threat to ecological safety due to their increasing accumulation in environments. The accumulation of REEs in environments has significantly increased its accumulation in the leaves of edible plants. However, the accumulation pathway of REEs in the leaves of edible plants are still unknown. In this study, lanthanum [La(III), a widely used and accumulated REE] and four edible plants (soybean, lettuce, pakchoi, and celery) with short growth cycles were selected as research objects. By using interdisciplinary research techniques, we found that low-dose La(III) activated endocytosis (mainly the clathrin-mediated endocytosis) in the leaf cells of four edible plants, which provided an accumulation pathway for low-dose La in the leaf cells of these edible plants. The accumulation of La in the leaf cells was positively correlated with the intensity of endocytosis, while the intensity of endocytosis was negatively correlated with the density of leaf trichomes. In addition to the accumulation of La, low-dose La(III) also brought other risks. For example, the harmful element (Pb) can also be accumulated in the leaf cells via La(III)-activated endocytosis; the homeostasis of the essential elements (K, Ca, Fe, Mg) was disrupted, although the chlorophyll synthesis and the growth of these leaf cells were accelerated; and the expression of stress response genes (GmNAC20, GmNAC11) in soybean leaves was increased. These results provided an insight to further analyze the toxicity and mechanism of REEs in plants, and sounded the alarm for the application of REEs in agriculture.


Assuntos
Endocitose/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Lantânio/metabolismo , Lantânio/toxicidade , Chumbo/metabolismo , Folhas de Planta/efeitos dos fármacos , Plantas Comestíveis/efeitos dos fármacos , Agricultura , Metais Terras Raras/metabolismo , Metais Terras Raras/toxicidade , Folhas de Planta/metabolismo , Plantas Comestíveis/metabolismo , Oligoelementos/metabolismo
6.
Sci Rep ; 10(1): 12657, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728170

RESUMO

Wind speed and variability are the most critical climatic factors affecting sand/dust storms, which have not been sufficiently studied in the middle reaches of the Yarlung Tsangpo River (MYR). In this study, wind speed variability was investigated using the moving average over shifting horizon method (MASH), combined with the modified Mann-Kendall test and Sen's slope based on data from the Tsetang, Lhasa, and Nyêmo meteorological stations during 1960-2015. The results indicated that annual wind speeds for the MYR wide valley regions declined significantly at decadal rates of - 0.216 m/s and underwent three stages from 1960 to 2015: an increasing trend from 1960 to 1975 (0.44 m/s per decade), a weakening until 2006 (- 0.46 m/s per decade), and a remarkable subsequent recovery (1.05 m/s per decade). Different variability trends were observed for the three stations: wind speed decreased significantly during all months at the Tsetang and Nyêmo stations, particularly in the spring, while for Lhasa, a non-significant wind speed increase was detected in summer, and the highest decline occurred in winter. The MASH method resulted in the effective visualization of different patterns, making seasonal process analysis and trend detection easier. In addition, the possible main causes for wind speed change were also discussed. The wind speed change in the study region was strongly associated with the large-scale atmospheric patterns, and the surface pressure gradient variability between the mid and low latitudes may have been a primary driving force. Positive/negative phases of the Pacific Decadal Oscillation (PDO) corresponded well with wind speed decreases/increases and were regarded as an indicator of wind speed variations. The effects of human activities associated with surface roughness change in the MYR were minor compared with the climatic changes.

8.
Aging (Albany NY) ; 12(7): 6401-6414, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32268299

RESUMO

The natural polyamine spermidine and spermine have been reported to ameliorate aging and aging-induced dementia. However, the mechanism is still confused. An aging model, the senescence accelerated mouse-8 (SAMP8), was used in this study. Novel object recognition and the open field test results showed that oral administration of spermidine, spermine and rapamycin increased discrimination index, modified number, inner squares distance and times. Spermidine and spermine increased the activity of SOD, and decreased the level of MDA in the aging brain. Spermidine and spermine phosphorylate AMPK and regulate autophagy proteins (LC3, Beclin 1 and p62). Spermidine and spermine balanced mitochondrial and maintain energy for neuron, with the regulation of MFN1, MFN2, DRP1, COX IV and ATP. In addition, western blot results (Bcl-2, Bax and Caspase-3, NLRP3, IL-18, IL-1ß) showed that spermidine and spermine prevented apoptosis and inflammation, and elevate the expression of neurotrophic factors, including NGF, PSD95and PSD93 and BDNF in neurons of SAMP8 mice. These results indicated that the effect of spermidine and spermine on anti-aging is related with improving autophagy and mitochondrial function.


Assuntos
Autofagia , Encéfalo/metabolismo , Senescência Celular , Mitocôndrias , Espermidina , Espermina , Animais , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Demência/metabolismo , Modelos Animais de Doenças , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Estresse Oxidativo , Espermidina/metabolismo , Espermidina/farmacologia , Espermina/metabolismo , Espermina/farmacologia
9.
Food Funct ; 11(3): 2489-2497, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32134423

RESUMO

Dementia is a kind of age-related neurodegenerative disease. Carnosine, an endogenous dipeptide consisting of ß-alanine and l-histidine, has been shown to have neuroprotective effects. However, the exact mechanism is still obscure. In this study, senescence-accelerated mouse prone 8 (SAMP8) mice, an age-related animal model, were used. Carnosine (100 and 200 mg kg-1 day-1) was orally administered to the mice once daily for six weeks. Behavioral tests, western blotting, and detection kits were used to evaluate the potential effects of carnosine on SAMP8 mice. Open-field and new object recognition experiments have shown that carnosine improved cognitive deficits in SAMP8 mice. Carnosine decreased the levels of malondialdehyde (MDA) and reactive oxygen species (ROS), increased the activity of superoxide dismutase (SOD) and the level of adenosine triphosphate (ATP) in SAMP8 mice. Concomitantly, western blotting results proved that carnosine increased the protein expressions of Mitofusin-1, Mitofusin-2, and Bcl-2 and reduced the protein expressions of P-Drp1, Bax, cleaved Caspase-3 and NLRP3 inflammasomes in the hippocampus of SAMP8 mice. The present data provided evidence that carnosine might improve cognitive impairment in SAMP8 mice through modulating mitochondrial dysfunction.


Assuntos
Envelhecimento/efeitos dos fármacos , Carnosina/farmacologia , Demência/tratamento farmacológico , Memória/efeitos dos fármacos , Doenças Mitocondriais/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Inflamação/tratamento farmacológico , Inflamação/fisiopatologia , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
10.
Aging (Albany NY) ; 12(4): 3175-3189, 2020 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-32065782

RESUMO

Alzheimer's disease (AD) is an age-related neurodegenerative disease. The main active component in Angelica sinensis, ligustilide, has been reported to have the protective effect on AD. Whether ligustilide could protect against age-induced dementia is still unknown. In this study, we used an aging model, SAMP8 mice to investigate the neuroprotective effect of ligustilide. The behavioral tests (Morris water maze, object recognition task, open field test and elevated plus maze) results showed that ligustilide could improve the memory deficit in SAMP8 mice. For mechanism study, we found that the protein level of P-Drp1 (fission) was decreased and the levels of Mfn1 and Mfn2 (fusion) were increased after ligustilide treatment in animals and cells. Ligustilide increased P-AMPK and ATP levels. Malondialdehyde and superoxide dismutase activity results indicated that ligustilide exerts antioxidant effects by reducing the level of oxidative stress markers. In addition, ligustilide improved neural function and alieved apoptosis and neuroinflammation. These findings have shown that ligustilide treatment improves mitochondrial function in SAMP8 mice, and improves memory loss.


Assuntos
4-Butirolactona/análogos & derivados , Envelhecimento/metabolismo , Inflamação/tratamento farmacológico , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , 4-Butirolactona/farmacologia , 4-Butirolactona/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Inflamação/metabolismo , Masculino , Transtornos da Memória/metabolismo , Camundongos , Mitocôndrias/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos
11.
Int J Biol Macromol ; 151: 47-55, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32035959

RESUMO

ß-Amyloid (Aß) plays an important role in the pathogenesis of Alzheimer's disease (AD). However, there is still no effective Aß-targeting drugs for AD treatment. In this study, we explored the effect and mechanism of Sodium Tanshinone IIA Sulfonate (STS) on AD. Aß-treated HT22 cells, an immortalized mouse hippocampal neuronal cell line, were employed. Different dosages of STS (0.1, 1 and 10 µM) were selected. STS improved cell viability and protected against Aß-induced apoptosis in a dose-dependent manner. Furthermore, the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) were decreased, while the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were significantly increased after STS treatment. STS decreased the levels of phosphorylate PKR-like (p-PERK), phosphorylate eukaryotic initiation factor 2 (p-eIF2α), phosphorylate inositol-requiring enzyme (p-IRE1α), X-box binding protein 1 (XBP1) and binding immunoglobulin heavy chain protein (Bip), while increased protein disulfide isomerase (PDI) levels in Aß-treated HT22 cells. In addition, the levels of insulin degrading enzymes (IDE) and Nepterrilysin (NEP) (or call it CD10) were significantly increased after STS treatment. Taken together, these results indicated that STS might be effective in treating AD via increasing the levels of Aß-degrading enzymes.


Assuntos
Peptídeos beta-Amiloides/efeitos adversos , Peptídeos beta-Amiloides/metabolismo , Inibidores Enzimáticos/farmacologia , Fragmentos de Peptídeos/efeitos adversos , Fragmentos de Peptídeos/metabolismo , Fenantrenos/farmacologia , Substâncias Protetoras/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/química , Peroxidação de Lipídeos/efeitos dos fármacos , Estrutura Molecular , Fenantrenos/química , Substâncias Protetoras/química , Proteólise/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
12.
Sci Total Environ ; 697: 134097, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31484090

RESUMO

Heavy metals inevitably cause invisible or visible damage to plants, leading to significant economic losses. Therefore, it is necessary to develop a method for timely monitoring the damage of plants under the stress of heavy metals. Here, vitronectin-like proteins (VN) on the surface of plant cells is as an important biomarker for monitoring damage of plants under the stress of heavy metals. A living plant cell-based biosensor is constructed to monitor invisible damage of plant cells induced by cadmium [Cd(II)] or lead [Pb(II)]. To fabricate this sensor, l-cysteine was first modified on the glassy carbon electrode followed by the modification of anti-IgG-Au antibody. Then, the living plant cells, incubated with the anti-VN, were modified onto the electrode. The sensor worked by determining the change in electrochemical impedance. Cd(II) and Pb(II) was detected in the linear dynamic range of 45-210 and 120-360 µmol·L-1, respectively. And the detection limit of Cd(II) and Pb(II) of this biosensor was 18.5 nmol·L-1 [with confidence interval (95%) 18.4-18.6 nmol·L-1] and 25.6 nmol·L-1 [with confidence interval (95%) 25.4-25.8 nmol·L-1], respectively. In both Arabidopsis and soybean, when the content of VN increased by about 20 times under the stress of Cd(II) or Pb(II), which means when the electron-transfer resistance increased by 35%, chlorophyll content showed significant decrease about 17%. Therefore, by establishing a quantitative relationship among the content of biomarker, the electron-transfer resistance and chlorophyll content in plant cells, the invisible damage of plants under the stress of heavy metals was detected. These results can provide a reference method for early-onset warning systems for heavy metal pollution in the environment.


Assuntos
Técnicas Biossensoriais , Metais Pesados/toxicidade , Células Vegetais/fisiologia , Poluentes do Solo/toxicidade , Metais Pesados/análise , Testes de Toxicidade
13.
IEEE Trans Neural Syst Rehabil Eng ; 27(5): 1032-1042, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30969928

RESUMO

Powered intelligent lower limb prosthesis can actuate the knee and ankle joints, allowing transfemoral amputees to perform seamless transitions between locomotion states with the help of an intent recognition system. However, prior intent recognition studies often installed multiple sensors on the prosthesis, and they employed machine learning techniques to analyze time-series data with empirical features. We alternatively propose a novel method for training an intent recognition system that provides natural transitions between level walk, stair ascent / descent, and ramp ascent / descent. Since the transition between two neighboring states is driven by motion intent, we aim to explore the mapping between the motion state of a healthy leg and an amputee's motion intent before the upcoming transition of the prosthesis. We use inertial measurement units (IMUs) and put them on the healthy leg of lower limb amputees for monitoring its locomotion state. We analyze IMU data within the early swing phase of the healthy leg, and feed data into a convolutional neural network (CNN) to learn the feature mapping without expert participation. The proposed method can predict the motion intent of both unilateral amputees and the able-bodied, and help to adaptively calibrate the control strategy for actuating powered intelligent prosthesis in advance. The experimental results show that the recognition accuracy can reach a high level (94.15% for the able-bodied, 89.23% for amputees) on 13 classes of motion intent, containing five steady states on different terrains as well as eight transitional states among the steady states.


Assuntos
Membros Artificiais , Intenção , Redes Neurais de Computação , Reconhecimento Psicológico , Adulto , Algoritmos , Amputados , Fenômenos Biomecânicos , Calibragem , Eletromiografia , Humanos , Locomoção , Aprendizado de Máquina , Masculino , Desenho de Prótese , Caminhada
14.
Nat Commun ; 10(1): 1399, 2019 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-30923311

RESUMO

Control of self-assembly is significant to the preparation of supramolecular materials and illustration of diversities in either natural or artificial systems. Supra-amphiphiles have remarkable advantages in the construction of nanostructures but control of shape and size of supramolecular nanostructures is still a great challenge. Here, we fabricate a series of supra-amphiphiles by utilizing the recognition motifs based on a heteroditopic porphyrin amphiphile and its zinc complex. These porphyrin amphiphiles can bind with a few guests including Cl-, coronene, C60, 4,4'-bipyridine and 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine, which are further applied to facilitate the controllable self-assembly. Addition of these guests result in the formation of various supra-amphiphiles with well-defined structures, thus induce the generation of different aggregates. A diverse of aggregation morphologies including nanospheres, nanorods, films, spheric micelles, vesicles and macrowires are constructed upon the influence of specific complexation, which highlights the present work with abundant control on the shapes and dimensions of self-assemblies.

15.
J Hazard Mater ; 365: 146-154, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30419461

RESUMO

Co-incorporated α-FeOOH nanocrystal (Co-FeOOH) was synthesized and applied for the ozonation of atenolol (ATL) in water. The compound was characterized and recognized as a transitional structure from FeOOH to CoFeO4. The presence of Co-FeOOH was observed to support the formation of •OH by promoting ozone decomposition, and the degradation of ATL and TOC was significantly improved during the catalytic ozonation. Catalytic reactions were rationally designed in different water matrices, efficient and simultaneous removal of ATL and natural organic contaminants was achieved. It was found that the reactions kinetics depend strongly on the solution pH which could alter the surface properties of catalyst and influence the ozone-decomposition. Based on the 19 organic intermediates identified by UPLC/Q-TOF-mass spectrometry, possible reaction pathways were accordingly proposed to elucidate the mechanism of atenolol degradation by ozone molecular and •OH. Three positions of ATL structure were concluded as the most vulnerable sites to be attacked by oxygen species to initiate the degradation path.

16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-802200

RESUMO

Objective:To study the protective effect of tetramethylpyrazine (TMP) on PC12 cells induced by tert-butyl hydroperoxide (t-BHP) and the regulatory mechanism on signaling pathway of phosphatidylinositol-3-kinases (PI3K)/kinase B (Akt)/mammalian target of rapamycin(mTOR). Method:PC12 cells cultured in vitro were treated with t-BHP (200 μmol·L-1) for 6 h to establish a model of oxidative damage in PC12 cells. The experiment was divided into blank group, model group (200 μmol·L-1t-BHP), TMP group. PC12 cells were pretreated with TMP(25, 50, 100 μmol·L-1) for 12 h, and then treated with t-BHP for 6 h. The cell viability was detected by cell counting kit-8(CCK-8) method, and lactate dehydrogenase (LDH) leakage, malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, reactive oxygen species (ROS) and glutathione peroxidase (GSH-Px) activity were detected by enzyme-linked immunosorbent assay (ELISA). Apoptosis was observed by annexin V-FITC/PI double staining. B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), total protein kinase B (Akt), and phosphorylated protein kinase B (p-Akt), mTOR and p-mTOR expressions were detected by Western blot. Result:The cell viability of PC12 cells treated with 200 μmol·L-1 t-BHP decreased to about 50%after 6 h. This condition was suitable for the establishment of oxidative damage model. Compared with the model group, TMP (25, 50, 100 μmol·L-1) pretreatment for 12 h significantly increased the survival rate of PC12 cells (PPPPPPP-1) pretreatment group increased significantly (PConclusion:Ligustrazine protects PC12 cell injury induced by t-BHP by activating PI3K/Akt/mTOR signaling pathway.

17.
Chemosphere ; 191: 946-953, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29145139

RESUMO

The feasibility of a bunch of screened psychrotrophs being applied to low-temperature wastewater treatment was investigated. The screened psychrophillic strains are capable of growth at a broad temperature-range from 0 to 40 °C and exhibit a preferable TTC-dehydrogenase activity at low temperature (4-10 °C). Along the sharply fluctuant temperatures (25-4-25 °C), the screened psychrotrophs (compared with the indigenous mesophiles) demonstrate less fluctuations of COD removal and more rapid recovery after temperature shocks. COD removal of approximate 80% was recorded by single psychrotrophs (while only 10% by single mesophiles) at low temperature (4 °C). Soft polyurethane foam showed better performance for psychrotrophs immobilization, with the optimal filling rate of 30% (v/v) in the bioreactor. The observation shows that the immobilized psychrotrophs demonstrated a relatively high performance on both conventional and emerging organic contaminants removals at low temperature. In order to check the feasibility of the screened psychrotrophs in treating actual domestic wastewater, a pilot-scale ICABR bioreactor was operated firstly at low temperature (4 °C) and then at seasonal varying temperatures (0-30 °C) for one year, the influent COD of 150-600 mg L-1 was efficiently reduced to 40 ± 18 mg L-1 under the conditions of an overall hydraulic retention time of 10 h. Furthermore, psychrotrophs performed stably as the predominant bacteria family during the whole operation. This study provides evidence that microbial intensification with psychrotrophs was a feasible strategy to improve the efficiency of conventional wastewater treatment process at low temperature.


Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Temperatura Baixa , Águas Residuárias/microbiologia , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Aderência Bacteriana , Reatores Biológicos/microbiologia , Clima , Ecologia , Poliuretanos , Estações do Ano , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
18.
Front Psychol ; 8: 1921, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29163298

RESUMO

In the field of emotion research, the influence of emotion regulation strategies on memory with emotional materials has been widely discussed in recent years. However, existing studies have focused exclusively on regulating negative emotion but not positive emotion. Therefore, in the present study, we investigated the influence of emotion regulation strategies for positive emotion on memory. One hundred and twenty college students were selected as participants. Emotional pictures (positive, negative and neutral) were selected from Chinese Affective Picture System (CAPS) as experimental materials. We employed a mixed, 4 (emotion regulation strategies: cognitive up-regulation, cognitive down-regulation, expressive suppression, passive viewing) × 3 (emotional pictures: positive, neutral, negative) experimental design. We investigated the influences of different emotion regulation strategies on memory performance, using free recall and recognition tasks with pictures varying in emotional content. The results showed that recognition and free recall memory performance of the cognitive reappraisal groups (up-regulation and down-regulation) were both better than that of the passive viewing group for all emotional pictures. No significant differences were reported in the two kinds of memory scores between the expressive suppression and passive viewing groups. The results also showed that the memory performance with the emotional pictures differed according to the form of memory test. For the recognition test, participants performed better with positive images than with neutral images. Free recall scores with negative images were higher than those with neutral images. These results suggest that both cognitive reappraisal regulation strategies (up-regulation and down-regulation) promoted explicit memories of the emotional content of stimuli, and the form of memory test influenced performance with emotional pictures.

19.
Chem Commun (Camb) ; 52(67): 10205-16, 2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27378382

RESUMO

The template-directed strategy is a powerful method to construct porphyrin nanorings with high complexities, wherein metalloporphyrin precursors pre-organize via supramolecular interactions of the porphyrin or its central metal with a carefully selected template, and then react with each other to deliver a final cyclic multiporphyrin structure. In this article, we review the recent breakthroughs in the template-directed synthesis methods and new structures of porphyrin or metalloporphyrin nanorings, as well as their applications in host-guest chemistry and artificial light-harvesting.

20.
Environ Sci Technol ; 43(14): 5481-7, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19708385

RESUMO

Previous studies have linked nitrosamine formation during ozonation to a nitrosation process in which nitrosation is catalyzed by formaldehyde, a normal byproduct of ozonation. This mechanism cannot explain the increase in N-nitrosodimethylamine (NDMA) formation with an increase of pH. This study reinvestigates the pathway of N-nitrosamine formation during ozonation. Our observations demonstrated the critical importance of some reactive inorganic nitrogenous intermediates, such as hydroxylamine and dinitrogen tetroxide (N2O4). We report two altemative pathways that possibly explain nitrosamine formation during ozonation at neutral and alkaline pH: (i) secondary amine precursors reacting with hydroxylamine to form unsymmetrical dialkylhydrazine intermediates, which are further oxidized to their relevant nitrosamines; and (ii) a nitrosation pathway in which N2O4 acts as the nitrosating reagent. The key variables of pathway (i) (including reaction time, pH, dissolved oxygen) were investigated. Since hydroxylamine is a common intermediate of dimethylamine oxidation, it is reasonable to assume that hydroxylamine is a possible inorganic precursor for NDMA formation during oxidation processes using strong oxidants. With an improved understanding of the pathway of nitrosamine formation, it should be apparent that the reactive nitrogenous intermediates play an important role in the N-nitrosamine-formation, so future studies of N-nitrosamine-formation control should be focused on the transformation of nitrogen in water treatment


Assuntos
Nitrosaminas/química , Ozônio/química , Poluentes Químicos da Água/química , Humanos , Hidroxilamina/química , Oxirredução , Oxigênio/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
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